On the eve of the first ever congressional hearing on proposals to repeal the Defense of Marriage Act (DOMA), the White House on Tuesday announced President Barack Obama’s endorsement of the Respect For Marriage Act — the bill that would repeal DOMA.

White House spokesman Jay Carney told reporters at Tuesday’s briefing that the president “is proud” to support the Respect For Marriage Act, “which would take the Defense of Marriage Act off the books for once and for all.”

The Respect for Marriage Act, introduced by Sen. Dianne Feinstein (D-Calif.) would repeal DOMA and restore the rights of all lawfully married couples, including same-sex couples, to receive the benefits of marriage under federal law.

Advocates of the repeal hailed the White House announcement.

“It is rare that a White House endorses a bill that has yet to pass first in either the Senate or the House,” said Rick Jacobs, chairman of the gay rights advocacy group Courage Campaign, in a statement. “His support makes clear to all Americans that the Defense of Marriage Act has no place in our society.”

“By supporting this legislation, the President continues to demonstrate his commitment to ending federal discrimination against tens of thousands of lawfully married same-sex couples,” said HRC President Joe Solmonese, in a statement.

On Wednesday, the Senate Judiciary Committee is scheduled to hear testimony about the marriage legislation.

The hearing, entitled “S.598, The Respect for Marriage Act: Assessing the Impact of DOMA on American Families,” marks the first ever hearing on the issue of repealing DOMA since its enactment nearly 15 years ago.

DOMA, enacted in 1996, prevents any of the over 1,100 federal rights, benefits and responsibilities of marriage from being afforded to legally married same-sex couples.

Those benefits include Social Security survivor benefits, federal employee health benefits for spouses, protections against spouses losing their homes in cases of severe medical emergencies, the right to sponsor a foreign born partner for immigration, the guarantee of family and medical leave and the ability to file joint tax returns, among many others.